Colombia’s navy captured five Costa Rican men on board a boat containing more than half a ton of cocaine off Colombia’s Malpelo Island in the Pacific Ocean Thursday.

According to a press release from Colombia’s naval forces, the boat is named Éxito 1 and was flying a Costa Rican flag. When officials boarded the boat, they found 626 kilograms of cocaine and 1,200 kilograms of illegally caught fish, including white sharks, albacore tuna, and black marlin, among others. Neither the five Costa Ricans nor one Nicaraguan passenger had any documents allowing them to sail or fish in Colombian waters, authorities said. The boat’s certifications, presumably from Costa Rica, were also expired.

The cocaine was stashed in hiding places around the ship within 31 rectangular packets. Authorities said they immediately tested the substance inside and results were positive for cocaine chlorhydrate.

The detained men have been transferred to the corresponding authorities in Buenaventura, Colombia.

Pedro Prada, the captain of Colombia’s Pacific Coast Guard unit, told a local paper there that the street value of 626 kilograms of cocaine is approximately $20 million. He said officers believe the boat was headed towards Central America to unload and possibly sell the drugs.